I. Field of the Invention
The present invention relates generally to powered kitchen receptacle closure removers for kitchen use. More particularly, this invention relates to surface mounted jar lid openers of the type classified in United States patent Class 81, Subclasses 3.2, 3.25, and 3.32.
II. Description of the Prior Art
It has long been recognized by those skilled in the art that there are many instances where manual removal of a jar lid is either not desirable or not feasible. For example, a lid may be too tightly installed during the manufacturing process, making it difficult to remove. Fluid trapped between the lid and the jar may also cause the lid to stick in a tightened position.
Even when the effort required to open a lid is within generally accepted limits, some people may still be unable to accomplish this task. Individuals suffering from arthritis or other joint afflictions or diseases, the young or elderly, and persons suffering from arm or hand injuries are all examples of individuals who may need assistance in opening a jar.
Numerous machines for unscrewing lids from jars have been proposed in the prior art. For example, U.S. Pat. No. 3,812,742, issued to Emil Polasek on May 28, 1974, discloses a jar opener with a pair of manually operated lever arms that adjustably hold the jar from the sides. A motorized upper gripping device must be manually lowered by the operator until it comes into contact with the jar lid. The operator can then activate a switch which causes the motorized gripping device to rotate the lid. When the lid is loosened from the jar, the operator must activate the switch again to stop the rotation.
U.S. Pat. No. 3,950,801, issued to Howard J. Morrison on Apr. 20, 1976, and U.S. Pat. No. 5,370,019, issued to M. Kevin Sartell et al. on Dec. 6, 1994, disclose two more typical jar lid removing machines. These inventions provide a manually operated, vertical locking device holding the jar clamped between upper and lower gripping devices. The upper gripping device is lowered into contact with the jar lid and locked into position. The motorized drive means of the lower gripping device is then actuated, causing the jar to be rotated relative to the stationary position of the lid.
Although similar in concept to the Morrison and Sartell patents, U.S. Pat. No. 5,430,923, issued to Donald G. Parent et al. on Jul. 11, 1995, differs in that operation of the device is fully automated. After placing a jar between upper and lower gripping devices, the user activates a switch which causes the lower gripping device to rotate as the upper gripping device descends until coming into contact with the jar lid. Once the lid has been loosened, the upper gripping device automatically returns to its raised position and rotation of the lower gripping device is stopped.
U.S. Pat. No. 5,617,765, issued to Vivian A. Bennett on Apr. 8, 1997, discloses a jar lid opener with a stationary lower gripping platform and a rotatable upper gripping device. After placing a jar on the lower platform, the operator activates a switch which lowers the upper gripping device until it comes into contact with the jar lid, whereupon the operator must once again activate the switch to stop the downward movement. The operator then activates a second switch which causes the upper gripping device to rotate, thereby loosening the jar lid, and activates the second switch once again to stop the rotation. Finally, the first switch is once again activated to raise the upper gripping device to its original position.
Another automated jar lid opener is disclosed in U.S. Pat. No. 5,353,665, issued to William D. Heebner on Oct. 11, 1994. In one embodiment of Heebner's invention, a jar is placed upon a stationary lower gripping platform. Upon activating a switch, an upper gripping device descends until coming into contact with the jar lid, whereupon it begins to rotate and loosen the jar lid. Upon sufficient loosening of the lid, the upper gripping device automatically stops rotating and returns to its original raised position. A second embodiment of the invention is also disclosed whereby the jar is placed upon a rotatable lower gripping platform. Upon activation of a switch, an upper gripping device descends until coming into contact with the lid, and the lower platform rotates until the lid is loosened.
Although many different types of automated jar lid opening machines have been disclosed in the prior art, these devices suffer a variety of shortcomings. Many of these automated devices still require some degree of manual effort on the part of the operator, thereby negating their usefulness to individuals with limited physical abilities. Other of these devices require that the operator control both the stopping and starting of the motorized components. If the operator does not stop movement of the device at the proper time, excessive force might possibly be applied to the jar, thereby causing breakage. Those inventions which disclose clamping devices for holding a jar while the lid is being rotated oftentimes do not provide an even holding force. In some cases there is no way to regulate the amount of force being applied to the jar and it is conceivable that excessive pressure might be applied, thereby breaking the jar. In addition, many of these holding devices are further limited in that they cannot accommodate a wide range of sizes of jars.
Furthermore, many of the aforementioned problems characteristic of prior art jar opener devices are aggravated by problems relating to centering. If a jar is inserted into conventional rotary opening apparatus without proper centering, the eccentrically rotated jar will improperly engage the internal gripping mechanisms. Therefore a means for centering the jar is highly desirable.